A phase shifter is a device capable of adjusting a phase of a wave. There are wide applications in such fields as radar, missile attitude control, communication, instrument and even music. The phase shifter, which organically combines transformer phase shift technology and the digital measurement technology, presents a high-precision phase shift adjustment, an accurate and visual reading, an adjustable output voltage and current, a favorable output waveform, a reliable operation and a convenient operation, so that the phase shifter can satisfy testing and checking of such instruments as single-phase and three-phase AC power and phase with a high precision, and can also be used in a test device of a meter.
In general, the phase shifter includes a wiper that presses against a PCB (printed circuit board) and is movable relative to the PCB to change a phase. It is known that, in an existing phase shifter, one end of the wiper is fixed relative to the PCB to serve as a center of rotation and the other end is rotatable about the center of rotation, thereby enabling the wiper to rotate with respect to the PCB.
The cost of the PCB is proportional to the area of the PCB; that is, the greater the area of PCB is, the higher the cost will normally be. Thus, a smaller phase shifter presents a cost advantage over a larger phase shifter. However, for a phase shifter, the use of the above-described rotary operation principle normally results in a larger size of the phase shifter, thus causing an increase in the cost.